The present invention relates to components of a system for remotely controlling a locomotive. More particularly, the system is characterized by the ability to accept voice commands from a human operator.
Systems for remotely controlling a locomotive are known in the art. For a reference, the reader is directed to the U.S. Pat. Nos. 5,511,749 and 5,685,507 that have been granted to Canac International Inc. on Apr. 30, 1996 and Nov. 11, 1997. Broadly stated, a remote control system for a locomotive has two main components, namely a lead controller and a follower controller. The follower controller is placed in the locomotive and it receives commands sent by the lead controller over a wireless communication link. The lead controller is in the form of a box or module that can be carried by a human operator located at a certain distance from the locomotive or the train pulled or pushed by the locomotive. When the operator would like to move the locomotive in a certain direction, he or she manipulates controls on the lead controller to dial in the desired parameters such as direction of movement, speed, etc. The command is encoded and sent by the lead controller over the wireless communication link to the follower controller. The follower controller processes the command and generates local control signals that are applied to the locomotive to implement the command.
The human operator that controls the locomotive remotely should at all times follow visually the movement of the locomotive such as to stop the locomotive if a hazardous condition suddenly develops.
Currently existing remote control systems for a locomotive use lead controllers that have manually operated controls. Stated otherwise, the operator must press switches, buttons or turn dials in order to enter the desired command. During the time necessary to operate the controls on the lead controller, the operator cannot visually maintain contact with the moving locomotive. For the reasons mentioned earlier, this constitutes a disadvantage. In addition, the hands of the operator are kept busy which prevents him from performing other useful tasks.
Against this background, it appears that there exists a need in the industry to develop a remote control system for a locomotive that limits or reduces the amount of time during which an operator must break visual contact with the moving locomotive in order to enter a command on the lead controller as well as allow greater flexibility in manual operations.
Under a first broad aspect, the invention provides a lead controller for use with a remote control system for a locomotive. The lead controller comprises an input, a processing unit coupled to the input and a communication link interface. The input is designed for receiving a signal derived from a spoken utterance. The signal is processed by the processing unit that generates data indicative of a command to be executed by the locomotive. The communication link interface is operative for transmitting the data indicative of the command to be executed by the locomotive to a follower controller in the locomotive where the command can be implemented.
Under a specific non-limiting example of implementation, the processing unit includes a speech recognition engine that attempts to match the spoken utterance to a vocabulary item in a speech recognition dictionary. The vocabulary item found to be the best match is then passed to a text-to-speech converter that synthesizes and audibly plays to the operator the vocabulary item found to match the spoken utterance. If the operator confirms that the speech recognition engine has issued the correct result (the spoken utterance has been correctly interpreted by the speech recognition engine) the command is implemented. Otherwise, no action is taken.
The advantage of this example of implementation over prior art designs is that the operator can supply commands to the lead controller by using voice and there is little or no necessity for him or her to break visual contact with the moving locomotive.
Another advantage is that the use of speech allows the hands of the operator be freed such as to allow him/her to perform other useful tasks.
In a second broad aspect, the invention provides a remote control system for a locomotive that has a lead controller remote from the locomotive and a follower controller that is designed to be mounted in the locomotive. The lead controller and the follower controller establish a wireless communication link between them. The lead controller includes an input for receiving a signal derived from a spoken utterance and, in response to this signal, derives from the spoken utterance data indicative of a command to be executed by the locomotive. The lead controller includes a communication link interface operative for transmitting the data indicative a command to be executed by the locomotive over the wireless communication link to the follower controller. The follower controller is responsible to the data indicative of a command to be executed by the locomotive for generating local signals for application to the locomotive to cause the locomotive to execute the command.